Wireless communications systems are used in a variety of telecommunications systems, television, radio and other media systems, data communication networks, and other systems to convey information between remote points using wireless transmitters and wireless receivers. A transmitter is an electronic device which, usually with the aid of an antenna, propagates an electromagnetic signal such as radio, television, or other telecommunications. Transmitters often include signal amplifiers which receive a radio-frequency or other signal, amplify the signal by a predetermined gain, and communicate the amplified signal. On the other hand, a receiver is an electronic device which, also usually with the aid of an antenna, receives and processes a wireless electromagnetic signal. In certain instances, a transmitter and receiver may be combined into a single device called a transceiver.
A receiver in a wireless communication device may employ a low-noise amplifier (LNA) to amplify a radio-frequency (RF) signal received by the receiver. In many instances, an LNA may be implemented as a broadband transconductance amplifier (TCA), configured to amplify RF signals over a wide range of frequencies. In traditional broadband TCA implementations, an input impedance magnitude of the broadband TCA (RP) and a quality factor (Q) associated with the input impendance may be relatively high at lower operating frequencies, but low for higher operating frequencies. Thus, for broadband operations at a wide range of frequencies, the gain and noise figure (defined as the ratio of the signal-to-noise ratio at the input of the broadband TCA to the signal-to-noise ratio at the output of the broadband TCA) may vary significantly over the wide range of frequencies.